On Wed, 30 Sep 2009 11:59:19 -0500 jeffrey Berger <[email protected]> wrote:
| I need to convert pdf files (which use a very limited palette of | colors) into gifs and use only the colors from the pdf file. The | problem seems to be that convert's antialias feature is introducing | many other colors. The resulting gifs have colors that are generally | 'muddier' than the originals. | | I've tried turning antialiasing off using +antialias. Didn't change | the output at all. I still get muddy colors. inspecting the output | with identify yielded exactly identical information. | | Also tried +dither with the same (non) result. | The real problem is that PDF's do not have a fixed 'resolution' or density. As such when ghostscript converts a PDF to an image the contains are resized to the resolution specified, and that needs anti-aliasing. You did no specify if the PDF data was a internal raster image, or just text. The later usually uses/needs anti-aliasing to make the text look better. The former (which by the tone of your request appears to be what you have) needs knowledge of the exact resolution of the raster image, which is NOT stored or provided by the PDF (as it is supposed to be resolution independent). So unless you have the EXACT resolution of the raster image stored in the PDF you will never get a perfect reproduction of the image, in either size or its colors. Anthony Thyssen ( System Programmer ) <[email protected]> ----------------------------------------------------------------------------- Who was to say that there weren't trolls in those tunnels, demons in those depth? Perhaps the real illusion of Dream Park was the pretense of technology. --- Niven and Barnes, "Barzoom Project" ----------------------------------------------------------------------------- Anthony's Home is his Castle http://www.cit.gu.edu.au/~anthony/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
